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Unfortunately the SLAC landmark server is really designed to be executed from a browser which will render the output, see for example http://www.slac.stanford.edu/cgi-wrap/traceroute.pl?function=ping&target=www.fnal.gov and view the source. Thus not only is it verbose (~3.3KBytes per successful request) but also EventHandler.pm has to carefully parse this human readable output to find the relevant ping output lines with the RTTs and losses. In addition the server uses the standard system ping command and its output which varies in details between OS's and releases so this also has to be accomodated accomadated in the parsing.
Logging
In addition to the normal web server (Apache) logging, we use Log4perl for logging. The configuration file is very simple. The following types of error messages can be found in the log file (this is at /scratch/tulip_log on wanmon.slac.stanford.edu).
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